What was a key philosophy held by the founding fathers

The founding fathers were religious men, but that was not their philosophy. Being men of education during their time, they were well read and took their philosophy from the idea of Natural Law. They believe as stated in the Declaration of Independence, that all men were created equal and that their Creator (who they called God) had given all men certain rights which could not justly be taken away.

This manifest itself in their view of use of government being to serve the people and the view that government must not interfere with the rights God had given. Hope this helps!!